Quickbooks Online randomly sending invoices and purchase orders

Thanks for reaching out to the Community, venusmf.

Since you've already confirmed you have no recurring templates set up for invoices or purchase orders, but they're still being sent without you sending them, I'd recommend checking your audit log. This log keeps a trail of records, showing who made changes to the books, and what they did.

Here's how to use it:
 

1. Sign in as an admin.
2. Use your Gear icon, then go to Audit log.
3. Click Filter and use the fields on your Filter panel to choose an appropriate User, Date, or Event to filter the results.
4. Select Apply.

Your audit log will display 150 records at a time. For most transactions and events, select View in the History column. This tells you who made a change, and what they did.

If you don't find record of a user sending the emails, but you still see them being sent somehow, you'll want to get in touch with our Customer Care team. They'll be able to pull up your account in a secure environment, conduct further research, and create an investigation ticket if necessary.

I've also included a couple detailed resources about working with your audit log and recurring transactions which may come in handy moving forward:
 

• Use the audit log
• Create recurring transactions

Please don't hesitate to send a reply if there's any additional questions. Have an awesome Tuesday!